Objectives: To study the effectiveness of yoga intervention on oxidative stress, glycemic status, blood pressure and anthropometry in prediabetes. Design: Randomized-controlled trial. Participants: Twenty nine prediabetes subjects aged 30-75 years. Setting: Yoga was conducted at 4 different community diabetes clinics in Mangalore, India. Interventions: Participants were randomized to either 3-month yoga or wait-list control groups. Main outcome measures: Malondialdehyde, glutathione, vitamin C, vitamin E, superoxide dismutase, plasma glucose, glycated haemoglobin, BMI, waist circumference, waist-to-hip ratio and blood pressure. Results: Yoga intervention resulted in a significant decline in malondialdehyde (p< 0.001), relative to the control group. In comparison with the control, there was a significant improvement in BMI, waist circumference, systolic blood pressure and fasting glucose levels at follow-up. No significant improvement in glycated haemoglobin, waist-to-hip ratio or any of the antioxidants was observed. Conclusions: Yoga intervention may be helpful in control of oxidative stress in prediabetes subjects. Yoga can also be beneficial in reduction in BMI, waist circumference, systolic blood pressure and fasting glucose. Effect of yoga on antioxidant parameters was not evident in this study. The findings of this study need to be confirmed in larger trials involving active control groups. (C) 2013 Elsevier Ltd. All rights reserved.

Context: Hypertension (HTN) is a chronic medical condition affecting nearly 1 billion people worldwide. Yoga, typically thought of as a series of physical postures, also includes breath practices and meditation. It has the potential to reduce of blood pressure (BP) through a combination of stress reduction and modification of the physiology of the autonomic nervous system. Pranayama is the art of prolongation and control of breath and helps bring conscious awareness to breathing patterns.Objectives: The study aimed to measure the effects of Sheetali and Sheetkari pranayamas on BP, the autonomic nervous system, and respiratory functions among hypertensive participants.
Design: The study design was a randomized controlled trial.
Setting: The study was carried out at a clinical research center at Sri Dharmasthala Manjunatheshwara Yoga and Nature Cure Hospital (Belthangady, India).
Participants: The participants were 60 hypertensive individuals, aged from 25 to 65 y, who were recruited from the general population located in and around Ujire, Belthangady, Karnataka, India.
Intervention: Participants were randomly assigned either to an intervention group (n = 30) or wait-list control groups (n = 30). The intervention included 2 types of pranayama breath practices (ie, Sheetali and Sheetkari) each practiced for 10 min/d.
Outcome Measures: BP and autonomic and respiratory functions were measured at baseline and postintervention.
Results: Compared to control, the intervention group showed a significant mean decrease in (1) systolic blood pressure (SBP)-16.2 mm Hg (P ≤.001), (2) respiratory rate-3.4 rpm (P<.001), and (3) heart rate-6.7 bpm (P ≤.01). Heart rate variability parameters were improved in the intervention group, including high-frequency power (P = .01), the number of pairs of successive NN intervals that differ by more than 50 ms (ie, NN50, P = .01), and the proportion of NN50 divided by total number of NNs (ie, pNN50, P = .05).
Conclusions: Sheetali and Sheetkari pranayamas appear effective for lowering SBP in individuals with HTN. Within-group results suggest that the changes may be mediated through a modification in tone of the sympathovagal nervous system.